Avengers AUs
by Sherlock Emrys
Summary: An assortment of oneshot fics from an AU prompt generator. All K , no pairings. Not just the Avengers, some other MCU characters make an appearance.
1. Chapter 1

**AN: So, I have exams, and instead of studying I elected to start writing fics from a random prompt generator. This is an AU Marvel-verse fic, based on a prompt where the villains and protagonists switch around. It doesn't have a proper ending because I ran out of steam. This is a one shot which will not be continued.**

* * *

_AVENGERS ATTACK AGAIN! s_creamed the newspaper headline, in block print.

_The shadowy group known only as "the Avengers" have struck again. New York was terrorised yesterday by a series of bank robberies perpetrated by the masked villains. The robbers were eventually…_

'Why do you still read that nonsense?'

Loki lowered the newspaper and raised an eyebrow. 'If you cannot understand the importance of knowing what your enemy is doing, I am not going to explain it to you.'

Red Skull drew himself up. 'Listen, you Asgardian oaf, I don't have to take that from -'

The communicator Loki had left on the countertop buzzed and the demigod snatched it up. 'Well?'

'The Avengers are moving again,' Doom's voice echoed through the speaker. 'Coordinates are in your comms. Go.'

'You got this?'

Natasha rolled her eyes and drew her gun, dropping two guards with practised efficiency. 'Of course I have this. Who do you think you are talking to, Clint?'

Clint grinned sharply and nocked an arrow, frying a camera without even looking. 'I'm talking to Naomi Brooks, Junior Clerk. Of course.'

Natasha sighed, adjusting the hang of her wig as she strode around a corner, heels clicking on the marble flooring. 'Next time, I leave you on the roof.'

There was a loud explosion.

'That's Tony,' Natasha said quickly.

'And that's our cue.' Clint hopped up on a handy plant pot and popped a ceiling tile, boosting himself into the crawlspace. 'See you in the archives.'

The courtyard was crowded. Tony surveyed it from a few hundred metres up with satisfaction. Plenty of civilians, plenty of screaming. Perfect distraction.

'I feel like heat-seeking missiles today,' he said aloud. 'What do you think? I feel like maybe people are getting too used to the repulsors.'

'Sir, your ego notwithstanding, repulsors are a more effective weapon here. They will cause far more instant chaos,' Jarvis responded.

A beat later Steve's voice sounded in his ear. 'Stark, just do whatever makes the most noise, mess and casualties. Distraction means distraction, not weapons test.'

'Distraction, weapons testing, what's the difference?' Tony said with a shrug. He glanced down at the courtyard and fired a few blasts. The screams sounded faint from this distance and he grinned. 'Fun and mass casualties either way.' Cutting the power to the flight stabilisers, Iron Man dropped like a stone and landed with a crash in the center of the courtyard, shattering the paving stones. He straightened up, bullets pinging off him, and took out three guards and a tree with a blast of the repulsors. 'Distraction is in progress. That's your cue, Hawkeye.'

'On it,' Hawkeye responded. 'Widow and I are on route to the archives, we should have the Hydra research files in five.'

'Make it three,' Steve cut in. 'We have Avengers coming our way.'

Tony swore. 'Send Thor.'

'His brother's going to get there first,' Steve said grimly. 'Get ready to take him out, Stark.'

'_Not _a problem,' Tony grinned, blasting the building's frontage with a missile. 'ETA?' There was a swirl of light in front of him and Tony rolled his eyes, jumping back into the air. 'Nevermind. I got him.'

Loki stepped out of the swirl of light with a grim expression and Tony rolled his eyes. 'Loki. Let me guess, we need to think about what we're doing.'

Loki raised an eyebrow and stepped forwards and off the ground, floating to Tony's height. 'You have one chance, Iron Man. If it were my choice, you would not even have that, but our fearless and overly moral leader has decided that scum that you need a warning.'

'Go to hell,' Tony said, and grinned fiercely. He spun, firing repulsors from both hands at Loki, who dodged them easily and shook his head.

'You were warned, Stark,' he said with a grin of his own.

Natasha jogged down the last corridor leading to Hydra's archives, her gun in one hand and her heels in another. She holstered the gun and slipped her feet into her shoes and turned the last corner, immaculate as always.

The last two guards stood in front of the doors. One of them stirred.

'ID, please, ma'am.'

Natasha smiled and held up the ID she had swiped from the desk of the head of Hydra's local research division. The guard glanced at it, then at her, and nodded, placing his hand on the blank wall behind him. The double doors slid open, and Natasha strolled through with a smile.

The doors closed behind her with a hiss, and she drew her gun, walking briskly through the rows of computer terminals .

The evac alarm sounded with a wail. Natasha sighed. 'Tony. What did I say?'

'Slightly busy – ow! – right now, Widow,' Tony snapped back at her through the comm. 'Loki's here and he's being kind of a spoilsport about the whole stealing data and selling it to the highest bidder thing.'

'Fine.' Natasha glanced around coolly and noted the lines of civilians hurrying for the doors. 'I'll deal with this.'

There were only three other people left in the archives now; herself, and two security guards. Natasha shot them without breaking stride and headed for the terminal she wanted, jamming the data drive into it.

'ETA, Widow,' Steve said tersely.

'Two minutes. I'm in, it's just downloading.'

A slight thud sounded from overhead and a ceiling panel vanished. Hawkeye landed on the ground behind her. 'Widow?'

'I'm on it. Going to need an overhead exit.'

'No problem.' Hawkeye glanced at the exit. 'You want those guards?'

Natasha glanced at the security guards from outside, who had clearly come to check on their buddies. 'Nope.'

Hawkeye coolly shot off two arrows, spearing them both between the eyes. 'Done.'

The courtyard was a scene of destruction, littered with rubble and bodies. Hydra agents scurried back and forth, calling for backup.

Red Skull strode out of the wrecked gates, glancing around with disbelief. 'And these guys are meant to be a government agency. Really? All it took was Iron Man?'

'Do not underestimate him,' Doom said cautiously, keeping place at his side. 'He is rarely seen without the rest of his little gang.'

As if on cue, there was a flash of lightning and a crash of thunder. Thor appeared at the other end of the courtyard, hammer swinging.

There was an almighty smash, and Iron Man was flung against the building, sending cracks scurrying through the stone. Loki landed heavily on the flagstones, glaring at his brother.

'I've got Iron Man,' Skull said quickly. 'You take Thor.'

Loki strode forwards, magic gathering around his hands. 'Thor.'

'Loki,' Thor said, malice glittering in his eyes.

'Brother,' Loki said quietly. 'Leave these foolish Midgardians. Come home to Asgard. Father will -'

'You think they would have me back?' Thor snorted in derision. 'You are deluded, _little brother_.'

Loki's face twisted. 'I am not of your blood, Thor, but I am more your father's son than you are. You have disgraced Asgard -'

With a roar, Thor flew at him, lightning crackling around his hammer.

Tony struggled upright, repulsors sputtering, eyes flicking over the data readouts. 'Jarvis, report.'

'Power at 80%,' Jarvis said coolly. 'I suggest running away, sir.'

'Screw that,' Tony said, confident. 'Redirect power, get me back on my feet, I have a demigod to take down.'

'I believe that his brother has beaten you to it,' Jarvis cut in.

Tony swore, and the repulsors ignited, bearing him aloft. A flicker of movement caught his eye and he spun into a dive, dodging a stream of bullets.

'Steve, I'm taking fire from Skull and Doom. Thor's got Loki for now, but we need an out.'

'Widow, status,' Steve snapped.

'Download complete,' Natasha responded quickly. 'We're on our way out. Iron Man, we need extraction.'

'I'll do my best. Steve, try and talk Thor out of beating his brother into a pulp today.'

'Go ahead, you try that, see how far you get. Hawkeye, you and Widow get to the extraction point and Stark will get you out.'

Natasha boosted herself up into the crawlspace, ignoring Clint's outstretched hand. She followed him through the cramped space, folding herself easily around the pipes and ducts filling the space.

'You OK back there?'

'Clint, if there was a problem, you would know about it,' Natasha said with a roll of her eyes. 'Put that bow away, you're going to take your own eye out.'

'Who's the expert on confined space again?' Clint glance back. 'Your wig is slipping.'

Natasha cursed and ripped the wig off, shoving it into her pocket. Her red hair tumbled down around her face as she swung herself around an air vent. 'How much further?'

Clint tilted his head and appeared to listen to something. 'Nearly there. Let's see…' He stopped and grabbed at a tile. 'This one.'

Natasha drew her gun and waited for him to remove the tile before dropping through, landing effortlessly on the balls of her feet and shooting a very surprised security guard before he could react. 'Clear,' she called.

Clint dropped down behind her and drew an arrow, hurrying up the stairs to the roof.

The roof was mostly intact where they were, and Clint lowered his bow, leaning against an air vent. 'Stark?'

'On my way.' There was a crackle of static and a swearword.

Natasha folded her arms and shook her head, slipping her heels back on and adjusting her tights, which had a slight ladder down one side. 'What?' she said in response to Clint's raised eyebrow. 'These are Louboutins. I took them from a dead fashion editor myself. They have sentimental value.'

'You are utterly terrifying. I just want you to know that. Also, fashion editor? That's a step down for you.'

'I didn't kill her, Clint, what do you think I am? Some kind of petty assassin?'

'No, you're a terrifyingly amoral assassin, obviously. So what happened?'

Natasha paused. 'I don't think you're ready to hear that story.'

'Not ready, yeah right. I've known you for years, woman, you can't possibly be more terrifying than I think you are.' Clint stretched his arms and slung his bow across his back. 'Here's our ride.'

Iron Man swooped towards them, weaving a little erratically and skittering across the roof on landing. Natasha surveyed him critically. 'I see you lost.'

'I'm sorry, who's giving who a ride here?' Tony demanded, straightening up. 'We need to be gone yesterday. Hop on.'

Clint pulled a face as he stepped up to Tony, slinging one arm around his shoulders and balancing on his foot. 'This is demeaning.'

Natasha rolled her eyes and stepped up, balancing perfectly in her Louboutin pumps and looking as demure as if taking the bus. 'It could be worse. He could be carrying you princess style.'

'Don't give him ideas,' Clint groused.

Tony coughed. 'Everyone ready? Hang on.' With that, he launched into the air with a whine of repulsors.

'Well, that went well,' Loki said, breaking the silence. He was nursing an angry looking burn across his forearm, green light gathering around his fingertips as he prodded it. 'Well done, team.'

'Thank you for your positive attitude,' Doom said with a glare. 'If you had not become so focussed upon your family problems we might have saved some of the data.'

'And some lives,' Red Skull said pointedly. 'Many brave Hydra agents died today.'

Loki scowled. 'My brother -'

'Quit trying to defend him, Loki, you know he's not worth it.' Magneto strolled in, pulling off his coat with a wince.

'Ah, the wanderer returns,' Loki said acidly. 'And where were you today? The Avengers attacked a Hydra outpost earlier, in case you missed it.'

'I was dealing with another problem,' Magneto said, holding Loki's gaze. 'Professor X and his rabble made an attempt to destroy a minor government building today.'

'Where?' Doom leant forwards.

'Jailhouse where a mutant man who had killed his partner was being held. They let him out, along with 300 other high-security prisoners.'

'Did you contain it?'

'Barely.'

Loki sighed. 'We will hear about this from Hydra high command, mark my words.'


	2. Chapter 2

AN: Here's another one.

**Prompt: A humorous scientist AU set in a post-apocalyptic world.**

* * *

It really didn't seem so bad, at first.

Sure, people were dying, but people died of swine flu, and nobody ever thought this would happen. Not really.

Steve supposed that all those folk stocking up for the end of the world must be laughing, right about now.

He hadn't ever studied it, he didn't know what it was, he wasn't a virologist for Pete's sake. He was an anthropologist. An explorer.

Maybe when society had recovered a bit he could go exploring again, maybe even write a paper.

The first few days when the virus had officially become an epidemic had been OK. He'd assumed they'd fix things up, and in the mean time, he could survive on his own. You didn't become an anthropologist specialising in tribal cultures without learning to live on leaves and bugs for a few days.

It was when he met Tony and Bruce that things changed.

Most of the population were dead at that point. Dead, or secondary vectors. Whatever the damn virus did to them, it was bad. A few days of rage-induced madness, and then horrible death. Half the casualties were people attacked by the vectors, and those they didn't kill they infected.

Steve was cautiously poking around an old supermarket, stocking up on non-perishables. And duct tape. It was amazing how many things that could fix.

And then he heard a crash, and a scream, and his heart jumped into his throat, because someone else was alive and out there, and they were being attacked by a vector.

He should have run, hidden, done something sensible. But then there was another yell, and a swearword, and a scream of rage and despair, and he didn't even think.

Slinging his pack safely behind an upturned cart, he sprinted towards the sound, casting around for something to use as a weapon. He still had his Glock, of course, but he didn't want to use that unless he had to. The vectors were still people, after all.

The noise was coming from the sidewalk outside the store, and Steve dived through the smashed window, looking for the vector. He grabbed the lid from an old trash can nearby, as though that would help, holding it like a shield.

The vector was standing in the middle of the street, and it was screaming.

Steve gaped for a moment. He'd never seen them act like that before.

A man was standing in front of it, hands out in front of him like he was trying to calm it down. He was scruffy, his hair sticking up at all angles, and he had the remnants of a goatee beard. He was wearing a tattered labcoat streaked with blood and engine oil, and he was waving at the vector.

'Get away from it!' Steve shouted at him. The man glanced over, eyes wide. 'It'll kill you!'

The vector roared, and the man gave a tight, stressed grin. 'Don't listen to him, Bruce, you're fine. Just take a deep breath, maybe some pills, jeez, just calm down, I'm not doing this again, remember last time? That was a good labcoat you ruined, you think they grow on trees?'

Steve shook his head. 'Listen, whoever he was, he's gone now. You have to leave him.'

The man glanced over again. 'Who the hell are you? And what makes you an expert all of a sudden?'

There was a crash. The vector had grabbed a whole lamppost and pulled it out of the ground, and was smashing a car with it.

Steve gasped and nearly dropped the bin lid. 'That… that's new.'

'Nah, that's just Bruce. He'll be fine.' The man sighed. 'I'm Tony. Social protocol presumably no longer applies, given that we don't have a society, so I'll skip the niceties and just ask you to go away and stop pointing that gun, jeez, where the hell did you get that? Put it _away_ before you hurt someone.'

'What… what is that? I've never seen a vector act that way before.'

Tony glanced over. 'What? Go green and start using the architecture as a play set? Yeah, Bruce isn't a vector. Mostly.'

'Mostly,' Steve said faintly. He shook his head. 'I'm sorry, you're the first human I've met in… I don't even know.'

'Same.' Tony shrugged. 'Yeah, Brucie here's a bit of a special case. He was trying to find a cure and it… backfired. I mean, he _is_ cured. In that he is not a vector. Unfortunately, whenever he gets stressed, that happens.'

They watched in silence for a moment.

'I guess he gets stressed a lot,' Steve commented.

Tony gave a one shouldered shrug and shoved his hands in his pockets. 'Mostly he pops beta-blockers all day and tries to stay calm. Some Zen stuff. It usually works.'

It was maybe a month after that that they found the base.

They had been exploring north, further and further, the lack of vectors boosting their confidence. The entire country seemed to be dead, except for them.

'Still no answer on international channels,' Tony announced. 'We are officially alone in the world, folks.'

Steve winced, prodding at his tin of beans. Bruce took a deep breath, but seemed unaffected.

'I'm checking the uptown district tomorrow,' Steve said to the table in general. 'Want to come with?'

Tony glanced up. 'Actually, I could use some more parts. They have a university lab there, should be some basics for a new telecommunications array. And if I can get tapped into the solar and wind farms, we get our power back, folks.'

'I'm so glad I survived the apocalypse with an engineer,' Bruce said with a faint smile.

'Want to come along? Maybe they'll have a biochem lab too. You could run some more of the figures on the virus.'

They never reached the university lab.

'Told you… we got… sloppy!' Tony panted between shots. 'I knew they couldn't all have gone.'

Steve shook his head, holding his makeshift shield in one hand and his own gun in the other. After the first time, Tony had adapted the bin lid – with several jibes and a litany of complaints about why he couldn't just build a superweapon – into a proper shield. Double reinforced, bulletproof, and lightweight, it was a dull silver circle, scuffed with use.

The vectors were slow, but they were angry. Really angry. Bruce was huddled behind them, breathing deeply, and they were backed up against a nondescript building. Tony glanced back at him. 'Hate to say it, Bruce, but we might need a hand here.'

The vectors pressed closer. Steve shuddered as their slack faces came into closeup, knocking them back with his shield.

Suddenly, the wall behind them disappeared.

'Come on in and hurry,' a terse female voice ordered. Steve was too occupied with the vectors to object, falling back quickly into the space. The wall slammed closed in front of them, and from this side he could see it was a hidden door, leaving the vectors to wail as they pounded angrily on the bricks.

Steve turned slowly, keeping his shield up. A red-haired woman, immaculately dressed, stood in front of them. She was a smart business suit, black pumps, and a semiautomatic on her hip.

Tony blinked a few times. 'Uh.'

'You'll have to excuse us,' Bruce said, in a clipped tone. 'We haven't actually spoken to a human for about a year.'

The redhead raised an eyebrow. 'It shows.'

'I'm Doctor Romanov, this is Clint Barton,' she explained in a businesslike tone as they entered what looked like a common room. 'I'm a clinical psychologist. He's a military specialist.'

A worn-looking man with sandy-blond hair nodded grimly at them.

'I'm Doctor Steve Rogers,' Steve said, nodding at them. 'Anthropology. This is Tony Stark -'

'_Doctor_ Stark. Or Master.' Tony paused. 'What do you call someone with four PhDs?'

'An egomaniac,' Romanov said without missing a beat. 'And you?'

'Doctor Bruce Banner,' Bruce said nervously. 'Biochem.'

'Well, aren't you all a well-educated little group,' Barton drawled. 'Whaddaya know, I guess a degree is good for something.'

Steve glanced around. 'What is this place?'

'Government base,' Romanov said offhandedly. 'We're the only ones left now. We have power, water and supplies. We can last out the century down here.'

'Someone was prepared,' Tony commented. Then, 'Wait, _now_?'

'You don't need to know about the others.'

'Some of them you met earlier,' Clint chimed in with a humourless grin.

'You got comms?' Tony asked.

'Yup. World's gone dark. We got a few islands, early on. Some of them are even still alive.'

'How many?' Steve asked urgently.

Romanov shrugged, face blank. 'Maybe a thousand. Globally. In this country? There's a base up in the middle of Canada somewhere, they were isolated enough to not get hit. Vectors didn't get above the snowline, they shut down the air filters and stayed down until the virus cleared. There's a team of six up there, running research.'

'That's it.' Steve felt like he needed to sit down. 'In America.'

Romanov gave him a glance that was not devoid of sympathy. 'Yes.'

'There are a few more in Europe,' Barton said flatly. 'There's a base in Cardiff. Then there are some isolated outposts – mountains, that kind of thing. Africa's nearly dead. There's only one group that we know of.'

'There may be more,' Romanov said gently. 'Not everyone has telecommunications. Us, and you. Maybe even lots more – lone survivors, a few groups. It's not over yet.'

'What can we do?' Bruce said quietly.

Romanov glanced at him. 'You're biochem? We have samples for you. You can try and find a reversal for those vectors up there. They're lasting longer than they used to. Simmons thinks that their bodies are adapting.'

'Simmons?'

'Canada base. She's biochem. Go take a look at the lab, Barton will show you how to contact her.' Romanov turned to the rest of the group. 'Stark. You're an engineer. We need to fix up some of our external systems. The purifiers were damaged in a vector attack last week, we've been struggling by on reserve water.'

'I'll fix it,' Tony said quickly. 'Do you have -' he descended into a stream of technobabble. Steve understood a few words occasionally.

Romanov blinked at him. 'There's… a toolkit in the R&D labs?'

Tony shook his head. 'I'll go take a look.'

Then he was gone, and Steve sat on the edge of a plush sofa, holding his shield in his hands.

'You're an anthropologist?' Romanov took a seat in the armchair opposite.

Steve smiled bleakly. 'It's not fair, is it? Anthropologists aren't the kind of people who should survive an apocalypse.'

She propped her chin on her hands and gazed at him. 'Why's that?'

Steve propped the shield against the sofa. 'I'm not useful. Tony can build things and fix things, Bruce knows what the virus did and how to treat it, you -' His eyes flitted to the semiautomatic. 'You seem to have a very unusual skillset for a psychologist, no offence, but things seem to have worked out. And Barton, I have no idea, he seems like he'd kill us all with his bare hands if he needed to. Me? I'm just… useless.'

'You survived this far.'

Steve found himself talking far more than he meant to. Maybe it was the fact that he hadn't spoken to anyone apart from Tony or Bruce for a year. Maybe it was part of Doctor Romanov's skill set.

'I only survived at first because I know how to live in the wild,' he explained. 'I mean, I specialise in tribal and isolated cultures, so I spent a lot of time in the jungle and the desert, you know… before. Knew what plants to eat, how to build a shelter, that kind of thing. Now? We're in a government base with enough food and power to last a century, and I have no business being alive. If someone else had survived, someone who could help put humanity back on its feet…' He looked up. Romanov was watching him with something approaching sympathy.

'Steve – Dr Rogers – did you ever consider that you survived because you were meant to? I mean, maybe it was fate, or maybe it was natural selection. Either way, you're not depriving anyone of the chance to live.'

'I know. But I feel so—so useless,' Steve said, twisting the shield in his hands. 'I can't do anything.'

Dr Romanov stretched her legs in front of her. 'Not yet. But you will. You and Tony and Bruce, how did you meet?'

Steve told her the story, feeling slightly foolish as he did so.

She nodded as he came to the end of it. 'You went to rescue a stranger from a vector.'

'I couldn't not,' Steve protested. 'I mean-'

'You risked your life for a total stranger, when nobody could possibly have expected you to.' Dr Romanov stood up and smiled. 'Steve, I think you're exactly the type of person humanity needs.' Her smile was warm, for once, as she held out a hand to help him up from the sofa. 'My name's Natasha.'

'Natasha,' Steve said, taking her hand as he stood. 'Nice to meet you, ma'am.'


	3. Chapter 3

**AN: It... got away from me.**

**I've been typing for about 5 hours non-stop now, and I just wanted to get the damn thing posted because seriously.**

**A revised version may be posted on its own at some point because this really is a full fic at this stage.**

**I'm way too tired to check the formatting so if it's screwy I'm sorry.**

**Fic 3 Prompt: A crime lab AU set in a futuristic sci-fi world. **

'Bruce, I need you to take this to Steve for me,' Tony called across the lab. With a flick of a hand he threw the file on his holographic screen to Bruce's, quickly grabbing his coat and heading for the door.

Bruce sighed and put down the vial of solution he'd been working on. 'Computer, pause. OK, Tony, why can't you take it yourself? This is the Trickster file, it's your analysis, and Captain Rogers is waiting for you to take it.'

Tony paused at the door. 'Because I am not going to be the one to hand this file over, you took it from me, it's yours now, now if you don't mind I have a date so bye -'

'Authorisation: Rogers, Steve,' the computerised door system announced coolly. Tony spun around as Steve strode in, looking preoccupied.

'Great, now you can tell him in person, bye!' Tony called, lightning fast, and made for the door.

'Going somewhere, Stark?' Steve interrupted, pausing in the doorway.

'It's the end of my shift, I have a date I'm late for, Bruce will give you the file you came for,' Tony gabbled, ducking past him.

Bruce sighed and shook his head, picking the vial back up again and turning back to the computer. 'OK, computer, give me the mass spec results on this sample and compare with the sample from suspect D and the factory records.'

'Analysing,' the computer said coolly, and Bruce tried to ignore the sounds of Tony and Steve arguing, again.

'Stark, I happen to know that your shift doesn't end for another thirty minutes. I know that because I checked before I came down.'

'Why can't you just pull up the results on your holo-cube like you're supposed to? You aren't even meant to be down here. If you used the System like everyone else, you could get the analysis as soon as I do.'

Steve sighed. 'You know I prefer to get the techs to explain it to me. How am I meant to make an investigation if I don't understand the evidence?'

'You realise that the computer would explain everything if you asked.'

'Tony, you're stalling.' Steve frowned. 'What is it about this analysis that you don't want to give me?'

Tony sighed and returned to his seat, twisting at the file on the holoscreen. An array of files unfolded across the screen. 'OK. The Trickster file. Here's the analysis from the first three bodies. You've seen those, you already made me explain them, three times, do I look like a computer to you? Seriously?'

'Stark.'

'Right, fine. Here's body number four.' He flicked at a folder of photographs, splaying them across the desk in a neat fan.

Steve glanced at them and Tony saw his face tighten. 'I know what it looked like. I was there.'

'Right. Right, sorry.' Tony swept them to one side and pulled up a series of graphs. 'So. Here's the DNA sweep – completely clean. Again. Which, by the way, I am beginning to take as a personal insult, because I helped to develop those scanners, and _nobody_ can walk through a room without leaving traces for me to find. Dead skin, hair, even the moisture of your breath. But no. So I'm guessing Trickster wears a hazmat suit and somehow nobody notices that. Because this time I swept the whole _building_ and cross-checked everyone against the Data Banks, and nobody went in there.'

'So what you're saying is we have no leads. Still.' Steve leaned over his shoulder. 'Even Romanov is drawing a blank here, Tony. We have to find something.'

'Romanov,' Tony said with great dignity, 'is not a scientist. Psych profiles are not science. They are guess work. Do not tell her I said that, she would kill me with a paperclip.'

'Probably,' Steve agreed. 'So we have nothing.'

'No. That's the worst part.' Tony looked unhappy, spinning two minimized files between his hands, nervously fidgeting. Steve didn't need to be a trained investigator to see that he had bad news.

'Stark…' Back to surnames. They'd known each other for years, but still Steve didn't feel happy with the informality Tony seemed to cultivate.

'See, the cameras drew a blank, as always, not that that means anything. Even infrared gets blocked these days, the new cloak techs are miles ahead of the public funding, these security cams are ancient, they've only got visual, night and infrared. Not even good night vision. Here's the footage from the room. See the lab techs leaving, like always, then this is the night shift of security. Next-gen clean energy is big money, so they have a lot of muscle on it, not that that helped. Last ditch defence goes inside, they shut the door. Nothing happens out here until morning, then the circus starts. Now take a look inside the safe.'

'They have cameras in there?' Steve said, surprised.

'No. No, they don't. That's the thing,' Tony said, tone clipped. He flicked the footage away, pulling up a new feed. It showed the victim, standing quietly beside a machine that held a blue cube. It was glowing.

'The cube?' Steve said curiously.

Tony shrugged. 'That's it. The Tesseract. Doesn't look like much, does it?'

'It wasn't there when I got there.'

'It was taken,' he said grimly. 'Wait and see.' Tony picked up a small device lying on his workbench. The holoscreen followed his movement and threw up infotags on the object. It looked a little like a camera.

Steve glanced at it. 'What is that?'

'Camera. Sort of. Prototype, I think, there's no records of it anywhere. It only has footage from that night. And they didn't put it there.'

'So who did?' Despite himself, Steve felt a surge of interest. Cases like this were no fun, but he couldn't help feeling just a little intrigued.

'Keep watching,' Tony said, subdued.

On screen, the victim – a stocky security guard in his early twenties, an atomiser slung over his shoulder, and one wrist augmented with a nice cyber-prosthetic piece, boosting punching strength by the looks of things, plus the distinctive stance of someone with a chest prosthesis (probably bulletproof) – suddenly started and turned. He drew the atomiser, but before he could even get his hand on the trigger, a figure seemed to appear out of thin air.

Steve winced and his hands clenched into fists. Tony glanced sideways and went to skip the feed, but Steve shook his head and stared fixedly at the screen.

'There's no sound,' Tony said quietly, looking away from the scene. 'Probably for the best.'

When it was over, Tony looked back at the scene. 'He's moving too fast during… the death to really get a look. But then, see. He stops. He looks right up at the camera.'

Steve was watching the feed, throat dry.

'I'm really sorry, Steve.' Tony stopped the video, dragged the image up and cropped it. 'But that's him. This is the Trickster.'

Steve shook his head. 'Can't be. He's been on leave for a week, ever since that incident in the Mars colonies.'

'Steve. He hasn't got an alibi for any of the crimes, and, well…'

Steve shook his head again, more insistent. 'Send this report to Romanov.'

Tony blanched, flicking the image off the screen and letting out a nervous laugh. 'Steve. Cap. You are not serious. That woman is beyond terrifying and there is no way that I am going to be the person who sends her the news that he's the Trickster.'

Steve just gave him his usual pained look. The one that said he was about to say something about Justice and Duty. 'Stark, she needs to know. I need her to find him and give me a psych eval ASAP, and then we need to find the answer here.'

Bruce spoke up from the other side of the room. 'Steve, Tony's right. We have footage of him murdering and – well, you saw – look, that is not the action of a sane man. And we need to bring him in, now. Put in a call to the Director, get him under control.'

Steve turned to face Bruce. 'Doctor Banner, I have no intention of arresting him at this stage. This is an ongoing investigation. I need that file sent to Romanov right now, Stark, or I will march you up to Ops myself and make you explain it to her in person.'

Tony threw his hands up in the air and spun the files together into a virtual folder, fingers darting across his holoscreen as he addressed the files and threw them into his outbox with more force than was necessary. 'Captain Rogers, are you seriously suggesting that you doubt the evidence of that video?'

'There is no doubt in my mind,' Steve said clearly, standing up and heading for the door, 'that Agent Barton is not the Trickster and he did not commit those crimes.'

Tony's shoulders slumped and Bruce let out a breath.

'Good,' Tony said, not looking at him. 'Me too.'

All things considered, Romanov took the news a lot better than expected. She sat at her sleek black desk, listening with a perfectly blank face to Steve's theory.

'Possible,' was all she said. 'But unlikely.'

Steve felt frustration building up as she waved a perfectly manicured hand through her holoscreen. 'You think he did this.'

She glanced up, her eyes meeting his. 'Not for a second.'

Steve let out a breath he hadn't realised he'd been holding. 'Good.'

'I've seen Stark's report,' Romanov said calmly. 'I agree with your recommendations. Barton is currently in his apartment on leave after the Mars incident.'

'You know where he lives?'

She rolled her eyes, so quick he almost missed it. 'I've been his partner for my entire career at SHIELD. Of course I know where he lives.'

'Do you want me to go with you?' Even as he said it, Steve felt stupid.

She gave a slight smile. 'Do you really think that's a good idea?'

'No. Not really.' Steve stood up. 'As of now, you and Barton are officially on my team on this case. I'll file the changes as soon as I get back to my office. Needless to say, the Director doesn't need to hear about this yet.'

Romanov stood up with him, coming around the side of her desk and following him to the door. 'You won't be able to keep this under your hat for long. This kind of evidence –'

'Investigating officer's discretion,' Steve said with a slight smile. 'I'm withholding for the sake of justice. SHIELD regs give me one week to tie this up before I have to hand it over.'

Romanov paused at the door, meeting his eyes. 'You'd better work fast, then, Captain Rogers.'

Tony liked this bar. It was his favourite kind of place. Sleazy enough that SHIELD wouldn't be hanging out here, but not so sleazy that they'd have to take an interest.

Plus, they served good drinks, and the bar fights were always entertaining.

Someone sat down on the barstool beside him, and he turned with a grin. 'Buy you a drink?'

'Since you asked, no,' Romanov replied smoothly. She tapped at the interface set into the cracked bartop, and the serving robot groaned into life. She watched fondly as it collected a glass. 'I always worry that someday that poor heap of circuitry is going to collapse into a rust heap when I ask it to pour me a drink.'

'Don't you believe it. That model will keep going through a nuclear apocalypse.' Tony downed the last of his whisky, grimacing slightly at the burn in his throat. 'So?'

'Not there,' Romanov said matter-of-factly. Tony glanced sideways, reading the slight tightness of her expression that showed her worry. She was wearing civilian clothes, a black biofeedback shirt and denim-look augmented leggings. He could just see the faint outline of the laser pistol at her hip. 'I checked his logs, he hasn't been back for a week.'

'He's only been on leave for a week,' Tony said, meeting her eyes. 'He must have left right after Mars.'

Romanov nodded. 'I didn't get to see him after Mars. I was in the Greater Germanic states, didn't get back for a day after he took leave.'

'He contact you?'

'No.' Romanov suddenly stiffened. 'How concerned are you about Captain Rogers?'

'I've been concerned about him for years, the man's work ethic is just not healthy. Plus, he doesn't drink. Who does that?' Tony frowned. 'Why?'

She smiled slightly, but didn't reply.

'Next time, Stark, notify me about team briefings,' Steve said, dropping onto the bar stool on Tony's other side. 'Through the System you're so fond of.'

Tony turned slowly back to face the front. 'Captain Rogers. There a reason you're here?'

'Little bird told me Romanov had intel.' Steve grinned. 'You can come sit down, Banner.'

Bruce leant on the bar beside Romanov, avoiding Tony's gaze. 'I had nothing to do with that.'

'Traitor,' Tony muttered. He turned to Steve. 'We have a problem.'

'Barton's gone.' Steve nodded. 'Thought he would be.'

'He's been compromised,' Romanov said smoothly. 'Since Mars.'

'We need to get a look at the files from the Mars mission.' Steve tapped at the interface and the robot creaked into life, depositing a glass of orange juice in front of him.

Tony eyed it with distaste. 'I can get access, but it'll take time. Fury has some serious problems with that mission, he's not letting anyone near the files.'

Steve frowned. 'Then how will you –'

'Drink your orange juice,' Romanov advised smoothly. She turned to Bruce. 'Can you access the sat feeds from a week ago?'

'Any satellite in particular?' Bruce asked drily.

She gave a slight, but undeniably vicious, grin. 'Any of them covering Mars? I need to find an anomalous energy spike matching the readings from over the lab on the night of the last killing.'

Bruce sighed. 'I was afraid you were going to ask me something illegal like that.'

'What do we have?' Steve called out as he headed into the office.

Tony looked up from his station, which had almost instantaneously become covered in coffee mugs and pieces of technology of uncertain origin and function. 'Problems. Many, many problems. Mainly, Fury is a paranoid, crazy person who has managed to put the most ridiculous security measures on his files.'

'I don't want to know,' Steve said, striding past him. 'If it's illegal, I didn't hear about it. Bruce?'

'It's illegal,' Bruce said, looking up from the data he was scrolling through with a laser stylus.

'Don't want to hear it,' Steve said, without breaking step. 'Romanov. You doing something that I can hear as a SHIELD agent, or do I have to pretend that none of you exist today?'

She looked up and raised an eyebrow.

'Pretend I didn't ask,' Steve said, seating himself at his own desk. SHIELD had whole rooms set up for temporary teams to work at, and Steve had booked one in for their little mismatched team.

Steve surveyed his team as he sipped at his own coffee. Tony had dived straight back into his computer, muttering to himself and the AI that he thought Steve hadn't noticed him sneaking into the system, dragging his hand through his already-messed up hair as the SHIELD logo bounced on the projection. The lab technician wore his usual ancient denim jeans (they'd recently come back into fashion, and apparently sim-fabric wasn't good enough for Tony) and a biofeedback top. The reactive panels glowed a bright blue, showing his stress and also, knowing him, lack of sleep and overdose of caffeine.

Bruce was standing in the centre of his holoscreen, surrounded by data fields and scrolling figures. He was frowning in concentration and using the laser stylus to isolate sections of a scrolling waveform as the computer offered suggestions. He was wearing a non-descript sim-shirt, cheap, not even a reactive fabric, and regular trousers. No biosensors, no tech.

Natasha was perched on her chair, the holoscreen glowing faintly in response to her fluid typing on a projected keyboard. Her red hair was curled over her shoulders, and she wore a SHIELD regulation bodysuit. Her holstered weapons were clearly visible under the elegant black coat that draped her slender frame.

There was an empty desk in the corner. Nobody was looking at it.

Tony growled in frustration and stepped back from his readings. 'This doesn't make sense. The Mars facility was experimental – clean energy, nothing more. Not even high-level data. Why is it buried under this level of –'

'Tony, take a look at these,' Bruce interrupted, throwing a screen across the room. Tony swiped aside the screen he was working on and enlarged Bruce's results. 'See the waveform in the delta spectrum?'

'That's a match,' Tony agreed, frowning at them. 'What the hell is this? I've never seen that pattern before.'

'It's a mix of stuff, all over the EM spectrum,' Bruce said nervously. Steve stood up and walked over to his station, taking a closer look. 'Plus some weird temporal residue. I only saw it because of the experimental systems being run by the EU –'

'Please don't say anything I'd have to repeat to Fury,' Steve said, frowning at the results. 'What is this?'

'This is the anomaly that was recorded when Barton appeared in the vault,' Tony said, already calling up other windows, running tests. 'And… this is Mars?'

'That's right,' Bruce said. 'The right place and time for Barton's mission. But it's like nothing that we've ever seen in this solar system.'

Steve shook his head. 'You're saying that this is some kind of alien?'

'I wouldn't go that far,' Tony said, standing back from the readings. 'I mean, let's not jump to conclusions. Could be an experimental prototype.'

'Or it could be magic,' Natasha said, her low voice cutting through the discussion. She stood up from her desk and moved closer to Tony's station.

Tony scoffed. 'Not that again.'

'You saw the reports, I take it,' she said, reaching out and tapping some figures.

Tony swiped his windows away from her. 'Yes, I did, and there's no way –'

'Barton and I were there.'

There was a pause.

'Was it really…' Steve began.

'It was magic, Cap,' she said simply. 'I saw it.'

'OK,' Bruce said, finding his voice. 'SHIELD's stance –'

'—has always been don't ask, don't tell,' Natasha said smoothly. 'They know magic users exist, they just don't want to blow the lid. The public would… not react well.'

'So it's magic,' Tony said slowly. The reactive panels on his shirt were shifting to green. Shock. 'How do we get Barton back?'

Natasha paused. 'I know a magic user.'

'Just to clarify,' Steve said, his voice sounding strange to his own ears, 'we've decided that Barton is in fact not a murderer but under magical mind control, and now we're going to ask a witch for help. I just want to be sure, so that when I write this up for Fury I can make sure he sends us to the right psychiatrists.'

'That's about right,' Tony said with a shrug. 'Guess it's time to sign out some weapons and go on a witch hunt.'

'Is that necessary?' Bruce said in a pained voice. Tony didn't turn to look at him. 'It is 100% necessary, and also this prototype needs field tests, and now seemed like a good time.'

'That's untested tech,' Steve said, unsure of even how best to yell at Tony this time.

'Only slightly. It'll be fine.' Tony shifted, and he clanked a little. The full-body armour was sleek; Steve had to give him that. It wasn't too bulky, and it looked nimble enough.

Natasha glanced back at them. 'We should be there soon.'

'Good.' Steve was feeling too big for the space, stuck in the back of Natasha's hovercar with Stark's armour jabbing him in the shoulder and Bruce crammed against the other window.

Natasha flicked some controls and the jets shifted, bringing them into dock on a seedy carpad. The neighbourhood looked distinctly rundown.

The hood hissed back, and Steve jumped out with relief. Stark clunked after him, the facemask snapping into place.

'You look like an idiot,' Natasha said, brushing past him as she led them towards a door.

'I do not.' Tony sounded offended through the suit's speakers.

Natasha paused at the door. 'I think you three should wait outside for now.'

Steve could feel a headache coming on.

The room was dark when Natasha slipped inside. Her biometrics had opened the door easily, but the room seemed to be deserted.

Seeming was not to be trusted around here.

'It's me,' she said calmly. She didn't bother to whisper.

A voice sounded out of the darkness by her ear. 'Natasha. How lovely to see you.'

She didn't flinch at the suddenness of the sound, although her hand itched for a gun. She was used to this by now.

'Stop grandstanding. I've brought guests.'

A sigh. 'So it is business that brings you to me. We never seem to – what's the phrase?—hang out any more.'

'Please never try to use slang again,' Natasha said quickly. 'And besides, you never let me find you for anything else.'

'I confess that I was not expecting you,' he said, and the lights came on suddenly, flooding the small building with a soft glow. She turned to face him. 'What disagreeable death has you seeking my assistance?'

'I'm looking for a friend,' Natasha said.

'Well, then you'd best bring your guests in,' Loki said with a smile.

The apartment was small, and cheap. It was furnished mostly with last-century electronics and lit by ancient LEDs.

Tony glanced around with an expression of slight disgust on his face. 'Wow. It's like a museum.'

'Tony,' Steve said warningly.

Loki sat at an old table, watching them with a raised eyebrow. 'Natasha, you seem to have quite the complement of friends already. Who are you looking for?'

'Agent Barton,' Natasha said squarely, seating herself opposite him. She held his gaze. 'He disappeared a week ago.'

A brief flicker seemed to cross Loki's face at that moment. 'I thought you told me that you did not have the gift. I fear you have been lying to me, Agent Romanov.'

She raised an eyebrow, not taking her eyes from his face. 'Loki. What do you know?'

'Know? Nothing. But yesterday I found a stray wandering around outside, apparently not quite himself.'

Natasha moved so fast that Steve didn't even see her draw a knife. Before he could blink, she had her knife to Loki's throat and a hand on the back of his neck. 'Where.'

'In the spare room,' Loki said coolly, apparently not disturbed by the blade at his throat.

'Steve,' Natasha said, not taking her eyes off the man.

Steve hurried to the door behind Loki, throwing it open cautiously. The spare room contained nothing but a sofa, some mouldering boxes, and Clint Barton.

He turned dull, incurious eyes towards Steve as he entered. 'Captain Rogers.'

'Barton,' Steve said, the word more of an exhalation.

Natasha let Loki go, subsiding into her chair. Bruce hurried around the table and guided Barton into the main room, where he began hurriedly to check him over.

'There was no need for that,' Loki said, sounding a little hurt. 'I have done your precious Barton no harm.'

'He's right,' Bruce said, gazing at Barton with worry in his eyes. 'There's nothing physically wrong with him.'

Natasha stood. 'Yes, there is.'

Tony took a step forward, the visor of his suit snapping down. 'Scan Agent Barton.'

The suit presumably obeyed him. Natasha stalked forwards, standing right in front of her partner.

'His eyes,' she said softly.

Barton looked at her stoically. 'Natasha.'

Bruce frowned. 'They're blue.'

Natasha tapped her wrist computer, throwing up a holographic picture and holding it out to Bruce without comment.

'Not usually,' Steve said with a grimace.

Tony let out a low whistle. 'He's coated in that radiation trace. The anomaly we found was definitely Barton.'

'What's wrong with him?' Natasha asked Loki, a faint edge of anger in her tone.

Loki stood up, following them around the table. Tony spared him a glance. Tall, rake-thin, and dressed in a green tunic and black trousers – no tech that he could see—and with black hair combed back from his face, he was striking.

'He has lost his mind,' Loki said in a low, musical lilt. 'Or rather, it has been stolen.'

'Who by?' Steve demanded. Barton just stood there. It was disturbing.

Loki shrugged.

'We need to get him back to SHIELD headquarters,' Steve said tightly. 'We can show that he wasn't responsible for the killings, we need to hand this in to Director Fury.'

'Your psychologists will not be able to help Agent Barton,' Loki commented.

Tony's faceplate flipped up and he pulled an incredulous face. 'Is this going to be another one of these magic things?'

'It is magic, Stark, whether you like it or not. Someone has control of his mind, and there is no way to release it without magic.'

'And you can do that?' Natasha demanded.

'Only the person who cast this spell can lift it. But I can tell you who that is.'

'Who?' Steve stepped forwards, wearing his Agent-of-SHIELD face.

Loki shrugged. 'I need to read the spell.'

'Do it,' Natasha snapped. Bruce glanced at her, wide eyed at this display of emotion.

Loki looked to Steve, who nodded, and then stood in front of Barton, one hand on the Agent's forehead.

Barton didn't react. Steve felt his throat tighten as he watched the man just stand there.

A glow built up under Loki's palm, greenish-blue, as though he had an LED embedded in his palm.

Stark crossed his arms. It was loud and awkward in the armour. His face clearly showed his incredulity.

Loki's eyes snapped open and he drew in a deep breath.

'Well?' Natasha said, one eyebrow raised.

'I was afraid of this,' Loki said quietly. He raised his head, lowering his hand, and made eye contact with Steve. 'It is my brother.'

SHIELD headquarters was dark. The work of justice never stopped, but it was definitely quieter at 1AM.

Steve strode along the corridors, his team behind him. The office door slid open at their approach, and they filed in without speaking.

Tony woke up his workstation with a swipe of his hand and began furiously manipulating files.

Natasha guided Barton to the centre of the room, nodding to Bruce, who hurried past her and powered up his own workstation, watching the MRI build a picture of Clint's brain sweep by sweep.

Loki filtered in behind them and loitered by the door, face shuttered.

Steve was already flipping through virtual files, calling up anything he could find on Loki's brother.

'Does he have a surname?' he called, staring in frustration at the scrolling files.

'I believe that in this world, he calls himself Odinson,' Loki said, his mouth twisting in discomfort.

Steve glanced up, raised an eyebrow, decided not to comment, and flicked aside his files, calling up a search refinement.

Bruce glanced up with a frown. 'This… is weird.'

'No kidding,' Tony said, glancing at the readouts. He rubbed his eyes. 'This is the weirdest week since that time with the jelly.'

'That was your fault,' Bruce said quickly.

'What thing with jelly?' Steve said absently.

'Nothing, nothing at all, absolutely nothing,' Tony said instantly, busying himself in his work.

'Is this another one of those illegal things I don't know about?'

'It's not illegal.'

'Just against SHIELD regs,' Natasha chipped in, standing at her desk.

Loki was following the back-and-forth with a frown. 'This is how you work?'

'Don't knock it, witch-kid,' Tony said absently. 'This is science. You may not have heard of it.'

Loki raised an eyebrow, but Steve interrupted his response. 'Wait, _that_ Thor?'

'By your tone, I deduce that you have the right Thor,' Loki said drily.

Tony glanced over his shoulder. 'Huh?'

Steve threw the data packet to their workstations, and Tony grabbed it and flicked it open. 'Woah, _that_ Thor?'

'Why is that everyone's response?' Loki said wearily.

Steve glanced up, brow furrowed. 'Thor is an agent of SHIELD.'

'He's a colleague of ours,' Natasha added, face blank as always.

Loki shrugged. 'He always was… personable.' He said it as though it were a disease of some kind.

'So, this is awkward,' Tony said, in his special I-don't-know-how-to-process-this tone. 'The Trickster killer being part of SHIELD.'

Natasha glanced at Steve. 'How do you want to handle this, Captain Rogers?'

Steve was drumming his fingers on the table, eyes fixed on the file. Finally, he stirred. 'We take this to Fury.'

'Let me get this straight, Captain,' Fury said slowly. 'You found that one of my agents had been filmed committing a violent murder. You kept quiet about it for three days, then decided that another, high ranking, SHIELD agent was actually controlling him with magic. And then you decided to come to me.'

'That's about the size of it,' Steve said in a clear tone. In his peripheral vision, he could see Bruce fidgeting, Tony looking as though he wanted to comment, and Natasha poised and unreadable as always.

Fury held his gaze for a moment, then sighed. 'I do so love the days like this.'

'You and me both, sir.' Steve shifted slightly. 'With your permission, sir, I would like to take Thor in for questioning.'

'Granted,' Fury said. 'And I want his brother in the cell next door.'

Natasha stirred. 'Sir, Loki helped us with our investigation voluntarily. I don't see – '

'We only have his word for it that his brother is responsible. Thor is a respected SHIELD agent and his brother clearly isn't his biggest fan. I'm not taking his word at face value.' Fury looked from Natasha to Steve, to Bruce, and to the clearly-incensed Tony. 'You are dismissed, agents.'

Thor came in quietly. He seemed more bemused than anything.

Until he saw Loki, being led into the holding cell by Natasha. That was when he got angry.

It took Steve and Tony in the new suit to hold him back and throw him into the holding cell. Loki just looked disdainful as his brother yelled.

The cell door slammed shut and Tony popped open the visor.

'I'm so glad we have noise-cancelling on these cells,' Tony commented.

Loki stepped up to the edge of the clear glass wall and tapped on it. Steve flicked the display to enable sound.

'How long must I stay here?' asked the mage. He seemed more irked than angry.

'Until Fury is happy,' Tony said with a sigh. 'So, you know, until Hell freezes over.'

'I'll try and get you out as soon as possible,' Steve promised. 'You're not being detained as a suspect. You're here as a material witness only.'

The bar seemed like a good place to go that evening.

'Case closed,' Bruce said dolefully, raising his glass of tea.

Tony scowled at the tea and drummed his fingers on the table beside his whisky glass. 'Why does nobody except me understand what alcohol is for?'

Natasha picked up her vodka bottle and tipped more into her shot glass without saying anything.

'Me and Natasha,' Tony amended.

Steve stared at his orange juice dolefully. 'This doesn't feel right.'

'Barton will be out of medical just as soon as they make Thor reverse the spell,' Bruce said reassuringly.

'That's not it,' Natasha said, a hint of frustration in her tone. She glanced at Steve. 'I agree. This was…'

Tony raised a hand. 'Oh, let me, please! I want to say it!' He cleared his throat and composed a serious expression. 'This was too easy.'

'Stark…' Steve said in frustration.

'Don't start.' Tony swallowed another sip of his whisky. 'I get it, Cap.' He lowered the glass and looked Steve in the eyes. 'This doesn't feel right.'

Bruce shook his head. 'Why would Thor have committed those murders?'

'He doesn't have alibis,' Natasha said smoothly. 'I checked.'

'Does Loki?' Steve said it before he could even think about it. Everyone looked at him in surprise.

'…No.' Natasha said after a moment.

They all looked at her.

'I checked him. It seemed like the thing to do.' She downed the shot of vodka. 'You all have alibis, if you were wondering.'

'You are a terrifying woman,' Tony said offhandedly, swallowing more whisky and grimacing at the burn.

'So why would Loki commit those murders?' Bruce said, leaning in as he began to think.

'He wants his brother out,' Steve said slowly.

Natasha shook her head. 'That's an incidental. Would be too clumsy.'

'Anyone can make a mistake.'

'Loki isn't clumsy,' she said quietly.

Tony glanced at her, then glanced back, and made a face. 'Tough week, huh.'

She rolled her head around and fixed him with a blank stare.

Tony made a face. 'O….K. Shutting up right about now.'

'No, this wasn't about Thor, not totally. What was the Mars mission about?'

Tony sat bolt upright. 'Oh.'

'What?' Steve said, sitting up. There was something in Tony's posture that was very much not good.

'I'm an idiot,' Tony said, staring into space.

'Not in dispute,' Bruce said with some concern. 'Tony?'

'Mars,' Tony said quickly. 'I found it, but then you found the spectrum and I forgot about it. Stupid!' The last word was almost a shout, and Steve glanced around the bar in concern. Their table was secluded, but this wasn't the kind of bar where you drew attention to yourself.

'Clean energy!' Tony glanced around the table, eyes wide. 'The Mars mission. It was investigating new energy sources.'

Steve felt the bottom drop out of his stomach. 'The last murder.'

'The Tesseract,' Tony said quietly. 'It was taken.'

'Clean energy,' Steve said quietly, shaking his head. 'That's what this was about?'

'Not exactly,' Natasha said in a low tone. 'The readings, Bruce, did you check them against that file I sent?'

Bruce nodded. 'It was a match. But what –'

'The Tesseract isn't just an energy source. It's what got Clint into that vault,' Natasha said quickly.

'But it was _in _the vault,' Steve said, confused.

'Like calls to like,' she said smoothly. 'Mars had the other piece.'

'There's two?'

'No, there were two halves. Now there's one,' Natasha said, making eye contact with them all in turn.

'Loki took the first piece from Mars,' Bruce said slowly.

'And he used Clint to take the second piece,' Tony completed. He looked at Natasha with respect. 'How did he get to Clint?'

'He was guarding the Tesseract on Mars,' Natasha said in a clipped tone. 'Fury sent him alone, because he thought nobody knew about it. Clint would have kept it safe while they fixed it into Mars' energy grid, and it would have been locked down safe for the next thousand years powering the colonies.'

'But Loki got there first,' Steve said, his face a mask of horror. This was it, he could feel it. The familiar feeling of solving a case roiled in his stomach – part excitement, adrenaline, fierce joy, and part sick guilt at finding happiness in other's suffering. Today it was tinged with fear and worry for Clint, and a horrifying revelation that they'd had the Trickster in their hands all along.

'And now he has the other half of the Tesseract.' Natasha looked around. 'This is bad.'

'Captain Obvious,' Tony mumbled, tossing back the rest of his drink.

'Loki's in the holding cells,' Steve said with relief. 'We have to tell Fury about this, but at least we know where he is.'

Natasha frowned. 'I hope it's that easy.'

At that moment, Steve felt his communicator buzz. He looked up at the table, and saw his own sudden fear reflected in their faces.

'No,' Tony said, flicking open the comm clasped to his wrist.

Natasha stretched her hand, watching the discrete ring on her middle finger whir into life. 'I refuse to believe that.'

Bruce fished a clunky old comm unit from his pocket and tapped a button. Steve pulled his own unit from his wrist, opening the message. It was a priority red.

'For future reference,' Tony said, staring at the message, 'nobody is ever allowed to say anything like that ever again. Ever.'

The SHIELD building was partly in flames by the time they got there. Natasha's hovercar screeched to a stop outside the entrance.

'Do you have the suit?' Steve called to Tony.

'Not here. It's in the office.'

'Go,' Steve ordered, and Tony took off running. 'Natasha. Find Loki. You know him best, talk him down.'

'I'll try,' she said simply, before slipping into the shadows.

'Bruce, find Clint,' Steve said, hurrying into the building. 'Wake him up, cure him, get him out.'

'You don't make it easy, do you?' Bruce commented, hurrying in the direction of the sickbay.

Tony hurried through the deserted corridors, half-sprinting. He spied the door of their office and broke into a run, skidding to a halt in front of the door. It slid calmly open for him, this section not having yet been sealed off under the fire protocols. Tony ran inside, heading for his suit, which sat on his desk in the form of a sleek silver box.

There was a hiss, a beep, and a flashing red light. The office door slid shut, the fire alarm wailing. Tony groaned. The fire must have reached this section.

He flipped open the lid and shoved his fists into the suitcase, grinning savagely as the suit unfolded itself around him.

'Now for a proper field test.'

Natasha slid silently though the chaos, heading for the screams and gunfire. Most of it seemed to be coming from Fury's office, which would appeal to Loki's theatrics.

She dodged a couple of panicked office workers, ignored an agent's shouted orders, and headed up another flight of stairs.

The office was nearly destroyed. The entire wall of windows had been blown out, along with the ceiling, leaving it essentially a rubble-strewn balcony. The door was pulverised, the furniture reduced to matchsticks.

Natasha silently picked her way through the destruction, edging her way further into the office.

He was standing in the centre of the ruined room, looking down at the burning building. A section collapse with a crash, and he laughed exultantly as the faint screams drifted up.

'Natasha.' He didn't turn around.

'It's me,' she said simply. There was no point trying to deceive him.

'How lovely to see you,' he continued.

'You can stop grandstanding,' Natasha said calmly, her gun in her hand. 'What do you want, Loki?'

'What do I want,' he said slowly. He seemed to be mulling it over. 'Why, I want to rule the world.'

'You don't have to do this,' Natasha said, edging slowly towards him.

He turned to face her, and the light of the fire lit his face. It wasn't the Loki she knew anymore. 'No,' he said, a slight smile twisting his face. 'I don't.'

Natasha dodged sideways. A millisecond later, an arrow landed in the ground where she had stood. 'Clint,' she said quietly.

Then she was off, jumping back and twisting into a somersault as she dodged two more arrows, landing on a chunk of rubble and pushing off, flying towards Clint, who stood there with blank blue eyes and his bow in his hand.

Steve ran through the corridors of SHIELD's headquarters, heading for his own office.

The door was locked shut. Fire protocols.

Steve smashed it with two kicks. They really needed to redesign some of the security features here.

He strode inside, grabbing his gun from the edge of the desk and slinging the belt around his waist. He didn't have time to change into his uniform. Instead, he shrugged off his leather jacket, pulling on his shoulder holster and then pulling the jacket on again, and stopped in front of the cabinet where the shield was stored.

It wasn't SHIELD regulation. And he was. But once upon a time, he'd just been Steve Rogers, and he'd been a soldier. His battalion had been an experiment. All the new equipment, all the new ideas, they got them first.

He was the only one left, now. And the shield was the last thing he had from the army, one of the experiments that had worked.

He never used it in SHIELD. Too many memories.

But this was big. He needed every weapon he had and that meant the one weapon he never wanted to wield again.

Steve slammed open the cabinet and pulled out the shield, settling it on his arm. The weight was familiar, and although he hadn't used it in years he knew in an instant that he could throw it as accurately as ever.

He turned back to the corridor and ran in the direction of the screams.

Bruce met the infirmary staff halfway. They were in full evac mode, wheeling patients and equipment out of the base.

'Barton,' he snapped to the first nurse he saw. 'Agent Clint Barton.'

He shook his head. 'Gone.'

Bruce felt the word like a punch in the stomach. 'Gone how?'

'Got up and left.' The nurse started walking again, wheeling his patient's bed towards the lift.

Bruce stood there for a moment, then cursed and pulled out his communicator.

'We have a problem,' crackled the communicator in his ear.

Steve turned a corner. 'We got several. What's your contribution to the list?'

'Clint's not in the infirmary. He walked out.'

Steve swore and doubled his pace.

Natasha landed hard and rolled, coming up firing. She got in three shots right at Loki's head, then she was moving again, dodging an arrow and blocking Clint's punch.

Loki threw up a shield and the bullets hit the ground in front of him.

Natasha caught Clint's fist and threw her own punch at his head, sweeping his legs out from under him with a kick. He ducked the punch and stumbled slightly, hitting the ground, but twisted and landed on her. She doubled her legs under his stomach and kicked up, throwing him backwards, and sprang to her feet. She ran, jumped, grabbed a girder exposed overhead and swung around it like a gymnast, planting her feet firmly in Clint's chest. He stumbled back, but turned the momentum into a handspring of his own and launched himself at her as she landed, knocking Natasha back onto the ground. She aimed a punch, which he blocked, pinning her arms above her head. She jerked her knee up into his groin, taking advantage of his recoil to throw him off her and put space between them, taking another two shots at Loki as she went past. He deflected them with amusement.

'Clint!' she yelled. 'I know you're in there.' She ducked an arrow and took off running.

He shot again, closer this time, an explosive that detonated at her heels, sending her flying forwards into a heap of rubble. She felt the brickwork tearing open her skin, and struggled to her feet, feeling the wounds stinging.

'Clint!' she yelled, as he ran towards her.

Loki laughed as he watched them struggle. 'He is mine now, Natasha. Do not bother trying to win him back.'

Natasha spared the energy to fire another shot at him. Dodging an arrow, she somersaulted back, scrambling to a halt on the edge of the ruined building. At her back, the seven-story drop loomed.

Clint walked towards her slowly.

'You see, Natasha,' Loki said lazily, strolling towards her, 'there's no satisfaction in simply killing. If there were, I would have killed Thor and the rest of you miserable humans long ago.' His grin widened. 'The fun is in the chase. Constructing a trap for your prey of their own making. You know how that feels, Natasha.' He was standing right by her now, grinning like a shark. 'And now, your precious Barton will die with you, and you will have the satisfaction of knowing that he killed you.' Clint was closer now, his bow slung across his back. He stopped, waiting. 'And before he dies, I shall free his mind. Just long enough that he realises what he's done.'

Natasha glanced from side to side. Loki stood one side, a wall the other. The drop was at her back, and Clint stood right in front of her, close enough to touch.

'It's almost a shame,' Loki said thoughtfully. 'We could have worked together, you and I.'

Natasha gave him her best persuasive look. 'We still can. You don't have to do this. Stand down, Loki, and we can fix this.'

'Tempting,' he whispered, his eyes piercing her own. 'But no.'

Clint lunged forwards, and Natasha felt his hands on her shoulders, and his body thudded into hers, and she tried to brace herself, but the sick feeling of gravity was already taking hold, and they tumbled back over the edge together into space.

Steve sprinted up the ruined stairs, skidding to a halt in the ruined office just in time to see Clint and Natasha fall.

'Natasha!' he yelled, running forward, knowing he was too far away.

They were gone, and Loki turned to face Steve.

'Captain Rogers,' Loki said, his voice full of malice. 'Just who I was hoping to-'

With a clang, Steve's shield whirled at his face and rebounded off his forcefield. Steve caught it on the rebound, bewildered.

Loki shook his head. 'Now, that was just rude.'

'Natasha,' Steve said, his voice thick. 'Clint.'

Loki paused. 'Oh, yes. Well, sacrifices must be made for progress, you know how it is.'

'Not today,' rang out a metallic voice from behind Loki, and Steve nearly dropped his shield.

Tony hovered just beyond the ledge, hands outstretched.

'It can fly,' Steve said faintly.

'You're not seeing this,' Tony said quickly. 'This is one of the things we don't share with Fury.'

'I think it's too late for that,' Natasha said, stepping onto the ledge from her perch on Tony's suit. She released her arm from around his shoulders and stepped off his foot onto solid ground. 'Thanks for the catch, Stark.'

Clint stepped from the other side of the suit, eyes no longer blue and looking very, very angry. 'Hi, Cap,' he said briefly, nocking an arrow. 'Sorry about that.'

'Agent Barton,' Steve said, relief clouding his tone. 'Agent Romanov.'

Loki grimaced. 'Well played, Stark.'

'I thank you,' Tony said, taking a bow in midair. 'Here all week, preferably not for catching folks who fall off ledges.'

They closed in around Loki, weapons up, not taking their eyes off him.

'Loki,' Steve said, shield at the ready. 'You are under arrest.'

'Worst. Week. Ever,' Tony said, raising his glass, squinting at the level of whisky, and then reaching for the bottle instead.

'Stark, if that's your worst ever, you should transfer to Ops for a while,' Natasha said, unruffled. Her cuts had been dressed and she sat a little stiffly in her chair, but she was otherwise immaculate.

'I don't know, it was pretty bad,' Clint said with a grimace. 'Also, Natasha, did you have to hit me that hard?'

'Yes.' She tossed back a shot of vodka and Clint paused.

'OK then.'

Bruce shook his head, cradling his tea. 'I know I wasn't there for the bad bit, but it still seems pretty bad.'

'Someday,' Natasha said, 'I will tell you all about Budapest.'

'You will not,' Clint said immediately. 'That is not something that Cap needs to hear about.'

'Why are you all so determined that I can't hear things?' Steve objected, finishing off his orange juice and signalling for another.

'You insist on reporting illegal things to Fury,' Tony informed him.

'That's because I'm a SHIELD agent.'

'It's not illegal when we do it,' Tony said sagely.

'Yes, it is,' Steve objected. 'In fact, it's almost certainly illegal _because_ you do it.'

'So, is Thor OK about the whole thing?' Tony said, changing the subject with alacrity.

'Amazingly, yes,' Clint said. 'I mean, he's being really nice about it. Apparently Loki did that kind of thing a lot when they were growing up.'

'Clearly they had very different standards of "psychopath" where they come from,' Tony grumbled.

'In other news,' Steve said, sipping his new orange juice, 'Fury has reassigned us all.'

There was a pause. 'That sounds bad,' Tony said cautiously.

'He was… intrigued by this investigation,' Steve said with a wry twist of his lips. 'He wants us to work together permanently.'

'Really,' Tony said, sceptical as always. 'He wants to put together two of his best Ops agents, his best and favourite maverick-loose-cannon lab tech, and his best pathologist all under Mr By-the-book.'

Steve shrugged. 'I didn't say it made sense.'

'What's he calling us? The Leftovers Squad? Loose Cannons R Us?' Tony snarked.

'Actually,' Natasha said with a slight smirk, 'He was going to call us the Avengers.'

There was a pause.

'Well, that's lame,' Clint said after a moment.

'Sounds like a superhero team,' Bruce agreed.

'Yeah, let's not do that,' Tony said quickly.


End file.
